MDL-21249 improved php docs and adding direct access prevention in portfolio

lib/portfolio/plugin.php

@@ -17,7 +17,7 @@
  * You should have received a copy of the GNU General Public License
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  *
- * @package    moodle
+ * @package    core
  * @subpackage portfolio
  * @author     Penny Leach <penny@catalyst.net.nz>
  * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL
@@ -29,6 +29,8 @@
  * See http://docs.moodle.org/en/Development:Writing_a_Portfolio_Plugin
  */
 
+defined('MOODLE_INTERNAL') || die();
+
 /**
 * the base class for portfolio plugins
 * all plugins must subclass this
@@ -114,7 +116,7 @@ abstract class portfolio_plugin_base {
 
     /**
     * override this if you are supporting the 'file' type (or a subformat)
-    * but have restrictions on mimetypes 
+    * but have restrictions on mimetypes
     *
     * @return boolean
     */